public static void Blur(Bitmap sourceImage, int radius)
{
if (GDIplus.IsBlurPossible(radius))
{
GDIplus.ApplyBlur(sourceImage, new Rectangle(0, 0, sourceImage.Width, sourceImage.Height), radius, false);
}
else
{
ImageHelper.ApplyBoxBlur(sourceImage, radius);
}
}
// 由指定bitmap创建一个新有带阴影的bitmap
protected Bitmap CreateShadow(Image sourceBitmap, float darkness, int shadowSize, Point shadowOffset,
out Point offset, PixelFormat targetPixelformat)
{
// Create a new "clean" image
offset = shadowOffset;
offset.X += shadowSize - 1;
offset.Y += shadowSize - 1;
Bitmap returnImage = ImageOperator.CreateEmptyBitmap(sourceBitmap.Width + (shadowSize * 2), sourceBitmap.Height + (shadowSize * 2),
targetPixelformat, Color.Empty, sourceBitmap.HorizontalResolution, sourceBitmap.VerticalResolution);
// Make sure the shadow is odd, there is no reason for an even blur!
if ((shadowSize & 1) == 0)
{
shadowSize++;
}
bool useGDIBlur = GDIplus.IsBlurPossible(shadowSize);
// Create "mask" for the shadow
ColorMatrix maskMatrix = new ColorMatrix();
maskMatrix.Matrix00 = 0;
maskMatrix.Matrix11 = 0;
maskMatrix.Matrix22 = 0;
if (useGDIBlur)
{
maskMatrix.Matrix33 = darkness + 0.1f;
}
else
{
maskMatrix.Matrix33 = darkness;
}
Rectangle shadowRectangle = new Rectangle(new Point(shadowSize, shadowSize), sourceBitmap.Size);
ImageOperator.ApplyColorMatrix((Bitmap)sourceBitmap, Rectangle.Empty, returnImage, shadowRectangle, maskMatrix);
// blur "shadow", apply to whole new image
if (useGDIBlur)
{
// Use GDI Blur
Rectangle newImageRectangle = new Rectangle(0, 0, returnImage.Width, returnImage.Height);
if (!GDIplus.ApplyBlur(returnImage, newImageRectangle, shadowSize + 1, false))
{
log.Error("Failed to ApplyBlur in GDIplus.");
}
}
else
{
// try normal software blur
ApplyBoxBlur(returnImage, shadowSize);
}
// Draw the original image over the shadow
using (Graphics graphics = Graphics.FromImage(returnImage)) {
// Make sure we draw with the best quality!
graphics.SmoothingMode = SmoothingMode.HighQuality;
graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;
graphics.CompositingQuality = CompositingQuality.HighQuality;
graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
// draw original with a TextureBrush so we have nice antialiasing!
using (Brush textureBrush = new TextureBrush(sourceBitmap, WrapMode.Clamp)) {
// We need to do a translate-tranform otherwise the image is wrapped
graphics.TranslateTransform(offset.X, offset.Y);
graphics.FillRectangle(textureBrush, 0, 0, sourceBitmap.Width, sourceBitmap.Height);
}
}
return(returnImage);
}
